1. Field of the Invention
This invention pertains to the field of tertiary 2-haloacetamides and their use in the agronomic arts, e.g., as herbicides.
2. Description of the Prior Art
It is known in the prior art to use various 2-haloacetamides as active ingredients in herbicides.
Among herbicidal acetamides of the prior art are those having a variety of substituents on the amide nitrogen atom including alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkoxy, halogen, aryl, etc.
Illustrative of the 2-haloacetamides of the prior art are those disclosed in U.S. Pat. Nos. 3,495,967; 3,901,917; 3,819,661; 3,946,045; and 4,012,222. All of these patents disclose 2-haloacetamides having a heterocyclic radical and hydrogen or an aromatic or aliphatic radical attached to the amide nitrogen.
U.S. Pat. No. 2,864,683 discloses 2-haloacetamides having one or more hydrogen, alkyl, alkenyl, alkynyl or halogenated analogs thereof on the nitrogen atom. U.S. Pat. Nos. 2,863,752 (Re. 26,961), 3,442,945, and 3,547,620 exemplify 2-haloacetamides having phenyl or substituted phenyl and hydrogen, alkyl, alkenyl, alkynyl or oxaalkylene radicals attached to the amide nitrogen atom.
More relevant to the 2-haloacetamides of this invention are those disclosed in U.S. Pat. Nos. 3,574,746 and 3,586,496. The 2-haloacetamides of these patents are characterized in relevant part by N-substituents of a 1-cycloalken-1-yl radical (which may be further substituted) and another substituent, which may include an alkoxyalkyl radical having up to 8 carbon atoms. These products are prepared by haloacetylating an N-(alkoxyalkyl) cycloalkylidene amine. However, that process is only amenable to producing 2-haloacetamides containing N-alkoxyalkyl radicals having no less than 2 carbon atoms between the amide nitrogen and ether oxygen atoms. This is amply demonstrated by the fact that no N-alkoxymethyl-substituted compounds are exemplified in the '746 and '496 patents. The reason for this is simple, viz, the N-alkoxymethyl cycloalkylidene amines required as starting materials to produce the corresponding N-alkoxymethyl-N-(1-cycloalken-1-yl)-2-haloacetamides do not exist. Nor do secondary N-(alkoxymethyl)-N-(1-cycloalken-1-yl) amines exist. Moreover, the primary alkoxymethyl amines necessary to react with cycloalkanones to produce such imines also do not exist. These theoretical starting materials either cannot be prepared or are so unstable they exist only momentarily as transitory intermediates.
Therefore, no known process of the prior art is capable of producing the N-(alkoxymethyl)-N-(1-cycloalken-1-yl)-2-haloacetamides disclosed and claimed herein. These compounds have now been made available by a new process disclosed and claimed in U.S. Application Ser. No. 896,879 filed Apr. 17, 1978, now abandoned, and further discussed below in the Detailed Description of the Invention.
It is, therefore, an object of this invention to provide a new class of 2-haloacetamides.
It is a further object of this invention to provide herbicidal compositions containing said new 2-haloacetamides as the active ingredient.
Still another object of this invention is the provision of a process for controlling undesirable weeds associated with dicotyledon and moncotyledon crops. Particular advantage is shown by some of the new 2-haloacetamides with respect to control of especially troublesome weeds such as yellow nutsedge, green foxtail, barnyardgrass and johnsongrass, while maintaining crop safety. Of particular advantage is the selective control of grass weeds in corn by certain herbicide species of this invention.